Background: High body mass constitutes a significant risk factor for morbidity and mortality in the general population, but it has been associated with an increased survival among dialysis patients. Its effects on renal transplant outcomes are controversial. The aim of our present work was to investigate the impact of high body mass and posttransplant weight gain on patient and graft outcomes.
Patients and methods: One thousand consecutive renal transplant recipients (631 men and 369 women) were included in the study. Their mean age was 42.9 years and the follow-up was at least 2 years. Basal immunosuppression was azathioprine (Aza) and steroids in 196 patients, cyclosporine (CsA) without or with antiproliferative agent in 557, and 239 were presented tacrolimus (Tac).
Results: At the time of transplantation the body mass index (BMI) was 23.7 +/- 3.9 kg/m2, namely, <18.5 kg/m2 in 6.3%; 18.5 to 25 in 61.7%; 25 to 30 in 25.4%; and >30 in 6.5%. Pretransplant obesity was associated with old age and female gender. Obese patients experienced a greater risk of delayed graft function (P < .01) and surgical wound complications (P < .01). After 1 year, 299 patients (29.9%) displayed weight gain >10% (mean 8.6% +/- 10.4% or 5.0 +/- 6.1 kg). Patients on Aza showed increased body weight by 11.9% +/- 10.9%; CsA patients by 9.5% +/- 10.3%, and Tac patients by 4.9% +/- 9.1% (P < .001). Univariate and multivariate analysis showed that pretransplant BMI had no effect on graft or patient survival either in the whole group or in the patients treated with CsA or TAC. Posttransplant weight gain above 5% or 10% did not influence graft or patient outcomes.
Conclusions: The new immunosuppressive regimes reduce posttransplant weight gain. Pretransplant high body mass and 1-year posttransplant weight gain were not risk factors for graft or patient survival in our experience.